This invention relates to liquid metal cooled nuclear reactor constructions.
In one well known example of liquid metal cooled nuclear reactor construction the reactor is submerged in a pool of coolant contained in a primary vessel. The primary vessel is housed in a concrete containment vault and is suspended from the roof of the vault. The core is carried on a diagrid which is suspended from the roof of the vault by tie rods and the roof carries control rods which are vertically insertable in the core to control reactivity. In the event of displacement of the core relative to the control rods during operation of the reactor core the resultant change of reactivity could have serious consequences and it is an object of the present invention to provide a construction of liquid metal cooled nuclear reactor having means for limiting uncontrolled displacement of the core relative to the control rods.